CalcMass Concrete Calculator
Last updated: 2026-05-09
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| Length (m) (m) | Width (m) (m) | Thickness (m) (m) |
|---|---|---|
| 3 m | 3 m | 0.1 m |
| 4 m | 4 m | 0.1 m |
| 5 m | 5 m | 0.12 m |
| 6 m | 4 m | 0.15 m |
| 10 m | 5 m | 0.15 m |
| 10 m | 10 m | 0.2 m |
What is Mass Concrete?
Mass concrete (also called plain or unreinforced concrete) is concrete without steel reinforcement. It's used for slabs, footings, pavements, heavy machinery bases, and retaining wall mass fills where compressive loads dominate and tensile stress is minimal. Unlike reinforced concrete, mass concrete relies on its own weight and compressive strength.
How to Calculate Mass Concrete Volume
Volume (m³) = Length (m) × Width (m) × Thickness (m)
The calculator multiplies the three dimensions to get total concrete volume in cubic meters. Then it estimates materials for a standard 1:2:3 mix:
- Cement: 7 bags (50 kg) per m³ of concrete
- Sand: 0.65 m³ per m³ of concrete
- Gravel: 0.90 m³ per m³ of concrete
Worked Example
A foundation slab measures 5m long, 3m wide, 0.20m thick:
- Volume = 5 × 3 × 0.20 = 3 m³
- Cement = 3 × 7 = 21 bags (50 kg)
- Sand = 3 × 0.65 = 1.95 m³
- Gravel = 3 × 0.90 = 2.70 m³
- Add 10% waste: order 23 bags cement, 2.15 m³ sand, 3 m³ gravel
Common Mistakes
- Using insufficient thickness (less than 15cm) leading to cracking under load
- Not ordering 5-10% extra for waste from spills and leveling
- Confusing cubic meters with square meters when ordering
- Using the wrong mix ratio for the application
Standards
Calculated per EN 206 / ACI 318. Concrete density used: 2,400 kg/m³.
Frequently Asked Questions
Mass concrete has no steel reinforcement. It relies on its own weight and compressive strength. Reinforced concrete contains steel bars that carry tensile forces, allowing longer spans and thinner sections.
Add 5-10% for standard pours. For irregular shapes or thin slabs, add 10-15% to account for cutting waste and spillage.
The calculator uses a standard 1:2:3 mix (1 part cement, 2 parts sand, 3 parts gravel) by volume. This produces concrete with approximately 25 MPa compressive strength, suitable for most residential and light commercial applications.